1. Field of the Invention
This invention generally relates to a recording paper monitor system for monitoring the status of recording paper for use in recording of data to be recorded, and, in particular, to a facsimile machine having a recording paper information memory which stores status information of the recording paper mounted in the facsimile machine.
2. Description of the Prior Art
As more and more facsimile machines are used, various kinds of recording paper, including thermal or photosensitive paper, are becoming available in the market. For example, such various kinds of recording paper have various sizes, including width and length, and various sensitivities in the case of thermal or photosensitive paper. Many of recent facsimile machines use thermal print heads and thus there is a large demand for thermal or photosensitive paper. However, since the sensitivity differs from paper to paper according to the manufacturing conditions, the photosensitive paper having the right sensitivity must be used in order to obtain printed images of high quality. However, none of the prior art facsimile machines were equipped with a detector for detecting the sensitivity of recording paper so that the recording paper can be known to be of the wrong kind only after having an image recorded thereon. In addition, most of the prior art facsimile machines require to use predetermined sizes of recording paper, so that they are normally equipped with a paper size detector for detecting certain paper sizes, such as A4 and B4, and if such a paper size detector detects the fact that recording paper of wrong size has been set, the detector activates an alarm device. Besides, in the case of roll paper, an end mark is typically provided at the trailing end of the paper so that an alarm signal is generated upon detection of this end mark.
FIG. 3 shows in block form the typical overall structure of a facsimile machine to which the present invention can be advantageously applied. As shown, the facsimile machine generally includes an image reader 1, a transmission buffer memory 2, a recorder 3, a reception buffer memory 4, a coder/decoder 5, a MODEM 6, a net control unit 7, an operation and display unit 8, a system controller 9, and a telephone 10. The image reader 1 is typically comprised of an image sensor, such as a CCD, which has a plurality of photoelectric elements arranged in the form of a single array sufficient in number to optically read an original 11 to be transmitted line by line. As is well known in the art, the longitudinal direction of the array of photoelectric elements and thus of the image sensor defines the main scanning direction of the image reader 1, and there is typically produced a relative motion between the image reader 1 and the original 11 to be transmitted in the auxiliary scanning direction which is normal to the main scanning direction. Thus, in one example, the original 11 is moved relative to the image reader 1 downwardly in FIG. 3 in the auxiliary scanning direction, during which the image reader 1 scans the original 11 in the main scanning direction line by line at a predetermined pitch. Thus, the visual image information of the original 11 is optically read by the image reader 1 and thus converted into an electrical image information. This electrical image information is typically subjected to a predetermined image signal processing, such as shading correction and binary conversion, at the image reader 1 and then output as image information to the transmission buffer memory 2. The transmission buffer memory 2 is typically comprised of a semiconductor memory and it temporarily stores the image information supplied from the image reader 1.
Also provided in the facsimile machine is the recorder 3 as an output means for recording received facsimile information on a sheet of recording paper 12, and the recorder 3 typically includes a plotter or any other type of printer, such as a thermal printer using a thermal print head and a laser printer. In the case of a facsimile machine, use is often made of thermal printers because they are small in size, durable, low at cost, and easy to maintain. In the case of using a thermal printer, use must be made of thermal or photosensitive paper for the recording paper 12. Alternatively, use may also be made of plain paper if use is also made of photosensitive tape as sandwiched between the plain paper and the thermal print head. The reception buffer memory 4 receives facsimile data which has been received and decoded and stores the facsimile data temporarily before being supplied to the recorder 3.
The coder/decoder 5 has a dual mode of operation. During transmission mode, the coder/decoder 5 encodes the image information supplied from the transmission buffer memory 2, thereby carrying out compression of data, for example, by the MH or MR method. On the other hand, during reception mode, the coder/decoder 5 decodes the received facsimile data to reconstruct the original image information to be sent to the recorder 3 via the reception buffer memory 4.
The MODEM 6 is provided to modulate the encoded facsimile data from the coder/decoder in a format suitable for transmission and also to demodulate the facsimile data upon reception before supplying the facsimile data to the coder/decoder 5. The net control unit 7 is provided to control a connecting condition with a transmission line and also the transmission and reception of a transmission procedure. The operation and display unit 8 is provided with various operational keys and displays, through which various information and instructions, such as telephone number of a receiver station to which data is to be sent, commands to initiate transmission, and operational commands to the reader 1 or the recorder 3, are supplied to the system controller 9. And, thus, this operation and display unit 8 serves as a man-machine interface in controlling the operation of the facsimile machine. The system controller 9 is typically comprised of a microcomputer and in charge of the overall control of the facsimile machine.
With the above-described structure, the original 11 is optically read by the image reader 1 and its image information is encoded, modulated and transmitted to a receiver facsimile machine at a remote station. On the other hand, when the facsimile machine received a transmitted facsimile signal, it is demodulated, decoded and recorded on the recording paper 12 by means of the recorder 3. In such a facsimile machine, however, the recording paper 12, such as roll paper, sheet paper or any other type, which is set in the recorder 3, cannot supply information regarding its size, width and length, and sensitivity by itself to the system controller 9. Therefore, the recorder 3 is typically provided with a A4 or B4 size detector for detecting the width of the recording paper 12 and an end detector for detecting the end mark provided near the end of roll paper. However, a detector for detecting the sensitivity of the recording paper 12 is not known and thus there is no way for detecting the sensitivity of the recording paper 12 automatically. Thus, the operator must determine the sensitivity of the recording paper 12 by inspecting its wrapping paper or the like before setting.